The past couple of heating seasons, my Rheem Criterion furnace has squeaked a bit on starting early in the morning. This morning, it squealed like crazy. I believe the squeal may be coming from the draft inducer motor. What's odd is that after squealing in the morning, it's fine for the rest of the day. Sometimes I will hear a "pinging" sound when the motor stops.

I opened up the burner compartment and had a look at it. The motor rotates freely, without making a sound. I don't see any place to lubricate anything. Is there something I can try, or do I need to replace it? If I need to replace it, can I just replace the motor, or does the whole assembly need to go?

First you need to be absolutely certain the noise you hear is from the inducer. No sense doing repairs or replacing the motor only to find you were incorrect in your assumption. Usually those small fractional horsepower motors come with sealed bearings. If the bearings are going bad you will either have to replace the motor or take the motor to a electric motor shop and see if they can replace the bearings.

Before doing anything make sure you identify the exact source of the noise.

I know for sure that it makes the noise before the ignitor lights. I guess I figured it could be the only thing moving at that time. It's tough to troubleshoot, since it only makes the noise once a day. I'll see what I can determine tomorrow.

If you're mechanically inclined, try and remove the whole inducer assembly. Then see if you can run 4 drops of 3in1 oil down the motor shaft into the front bearing. You may buy enough time to get through the heating season more quietly.

Also with the assembly off, get all the data off the motor (make, model etc) so you can find a replacement or seek the help of an electric motor shop. Sadly a new motor may be less expensive. Note how the motor shaft attaches to the small blower wheel (squirrel cage). You may need a allen wrench or other tool to remove it from the shaft. Good luck.